Method of making bags or envelopes



Aug. 13, 940., J. J. BRELL Er AL.

METHOD OF MAKING BAGS OR ENVELOPES Filed March 11,1939

Patented ug. 13, 1940 G BAGS (BR ENVELGPIES Delaware Application March ll, 1939, Serial No. 2613M 12 Claims.

This inventionrelates to bags, envelopes and other similar containers, and more particularly tosuch containers as are made from thin, relatively destructible sheet material such as paper, and more especially the well-known transparent material known commercially as Cellophane .and by other trade names.

One of the objections generally encountered in bags and envelopes made of Cellophane and similar materials is the tendency of such containers to easily tear or split at the mouth of the bag or envelope during the insertion or removal of the bag contents, and as is well known, a slight tear in an envelope of this material at once results in they almost immediate complete destruction of the envelope as the tear spreads rapidly once it starts inwardly from the mouth-edge of the envelope. It is of course, possible to reinforce the mouth-edge of such bags by the application of a so-called binding, but such bindings separately applied by hand or by machine at once make the cost of the bags or. envelopes prohibitive and limit their use in the trade con-- siderably.

One of the objects of the present invention is to provide a bag which shall be strongly reinforced at its mouth-edge so that tearing of the bag inwardly from the mouth-edge will be effectively prevented, the reinforcement so provided consisting of a reinforcing element constituting an integral portion of the body of the bag.

Another object of the invention consists of an improved method of bag manufacture by which reinforced bags or envelopes of the character herein described may be'speedily and efiectively manufactured by ordinary, readily-available, bag-manufacturing machinery, and the reinforced bags may be manufactured at a cost comparable to those of conventional unreinforced, readily-destructible, construction.

Another object of the invention consists in the provision of a novel pleated strip or web which, when fed to blank-cutting mechanism of conventional construction, will result in the severance of blanks from said web, each provided with a reinforced edge that subsequently forms the strongly-reinforced mouth-edge of the bag prostrip showing the folds or pleats flattened down and having their contacting surfaces adhesively united; Fig. 4 is a face view of one of the bag or envelope blanks cut from the strip. Fig. 5'is a view of the rear face of a completed envelope or bag; Fig, 6 is a sectional view on the line 66 of Fig. 5, looking in the direction of the arrows; Fig. 7 is a sectional view on the line il of Fig.

5, looking in the direction of the arrows; Fig. 8 is v a face view of the strip, showing the same formed with a single longitudinally extending fold or pleat such as is employed when the blanks are cut' transversely of the strip, and Fig. 9 is a perspective view of one end of the strip shown in Fig. 8.

With reference to the strip shown in Figs. 1 to 3 inclusive: The strip is preferably a lengthy element composed of sheet material, such as that commercially sold as Cellophane and under other trade names, provided in the form of a roll from which it is unwound as required and it is, in conventional bag or envelope manufacture,.fed to cutting rollers by which the bag blanks are cut from the strip fed between them. The bag or envelope blanks, of conventional outline, are indicated in dotted lines at 3 in Fig. 1. In carrying out our invention we form the strip with a plurality of equally spaced, transversely extending, pleats or folds as indicated at 2, and adhesively unite the layers or contacting portions of these folds, before the strip is fed to the cutting rolls or other blank-forming mechanism. By means of suitable folding mechanism, the strip'l is formed with the Z-shaped folds or pleats 2 at suitably spaced intervals, the spacing of the folds from one another being dependent upon the size and shape of the envelope or bag blanks to be subsequently cut from the strip. After the strip has been provided with the spaced transverse folds 2, as clearly shown in Fig. 2, the overlapping portions or layers of the folds are adhesively secured together so that the resultant strip appears as shown in Fig. 3. The adhesive attachment of the several folds can be attained by means of an adhesive material ll applied on the surfaces 4 and of each fold or it may possibly be secured by the application of heat applied over the folds to unite the layers of the same. Therefore, in herein referring to the adhesive attachment of the layers of the folds, I do not wish to be limited to the employment of a liquid or other separate adhesive applied to the surfaces of the folds since the application of heat applied over the folds may be sufficient to unite the fold layers.

When the layers of the folds have been united in the manner explained, which operation can be facilitated by feeding the strip between pressing rolls, the strip is next fed to cutting dies or cutting rolls which act to cut out the blanks 3 from the strip. In severing each blank from the strip, the cutting is so performed that the resultant severed blank has its top edge, or mouth-forming edge made up of the triple-layered pleat or fold 2, as shown in Fig. 5. The blank from which the bag or envelope is produced is provided with the side flaps l and 8, a bottom flap 9 and the closure flap 6, said flap 6 forming a continuation or upward extension of one of the layers of the pleat as will be clearly seen in Figs. 6 and 7. Flaps l and 8 are inwardly folded in the conventional manner on the lines I0 and. adhesively united in overlapped relationship and bottom flap 9 is folded upwardly on the line l8 and adhesively secured down on top of the overlapped side flaps 1 and 8.

In the finished bag or envelope, the entire top edge of the mouth of the bag is reinforced by the triple-layered fold or pleat. Thus it is almost impossible to tear the mouth edge of the bag or envelope. Since the strip l is preferably, but not necessarily, composed of Cellophane or some similar completely transparent material, the thickened top edge of the bag at the mouth of the same is either invisible or nearly so and accordingly does not in any way detract from the appearance of the bag.

In cutting out the bag blanks from the strip by the use of rotary cutting knives or cutting rolls, the registration of the knives with the pleats, to insure proper cutting of the blanks, can be simply attained, since the pleats form projections on the strip for engagement by a feeler to thereby register the strip for the cutting of each blank. Therefore, the feeding of the pleated strip to cutting rolls for the cutting-out of bag or envelope blanks in the conventional manner presents no real manufacturing problems.

In the embodiment of the invention shown in Fig. 8 is a strip l5 composed of any suitable sheet material such as Cellophane or the like. The strip is formed with a single, longitudinally extending, off-center Z-shaped fold or pleat I4, the same being produced, and having its overlying layers adhesively united, in the manner explained with reference to the pleats disclosed inthe strip of Fig. 1.' In severing blanks from the strip l5,

said blanks are cut across the strip, or in other words in a direction at right angles to those cut from the strip I of Fig. l. The fold or pleat l4 forms the top edge or mouth-forming edge of the bag blanks, the bag blank or envelope blank so produced being similar in all respects to that shown in Fig. 4 except that it is cut across the grain of the Cellophane strip rather than in the direction of the same, it being well understood in this art that such material has a so-called grain or resistance to tearing greater in one direction than in an opposite direction. Otherwisethe description heretoforegiven of the blank, and bag or envelope formed therefrom, applies to the blank cut from the strip l5.

While we have herein described a bag blank of a certain shape, it will be understood that the shape of the blank and the bag or envelope to be formed therefrom is dependent upon the use to which the bag is to be put and we do not wish to be limited to any specific blank or bag shape.

In carrying out the present invention, no special or expensive machinery in addition to that ordinarily employed in bag or envelope manufacture need be required, since the operations of forming the strip with the pleats and adhesively uniting the pleat-layers can be readily performed with simple devices either readily attached to present machines or used supplemental thereto.

What we claim is:

1. In the method of making envelopes, bags and similar containers, the steps of forming a section of sheet material with a pleat, uniting the layers of the pleat, and cutting an envelope or bag blank out of the section so that the mouth of the envelope or bag formed from said blank will be surrounded and reinforced by the united layers of the pleat.

2. In the method of making envelopes, bags or similar containers, the steps of forming a strip of sheet material with a pleat, intimately attaching the superposed layers of the pleat together, and cutting an envelope or bag blank out of the strip so that the mouth of the envelope or bag formed from said blank will be reinforced by the united superposed layers of the pleat.

3. In the method of making envelopes, bags or similar containers, the steps of forming a lengthy strip of sheet material with a pleat, adhesively uniting overlying layers of the pleat, and cutting out an envelope or bag blank from the strip with the united layers of the pleat disposed along one edge of the blank, and folding the blank to form it into an envelope or bag with the mouth of said envelope or bag surrounded by the united overlying layers of the pleat.

4. In the method of making envelopes or bags the steps of forming a section of sheet material with a Z-shaped pleat, uniting by adhesion the layers of the pleat, and cutting out an envelope or bag blank from the sheet with the Z-shaped pleat disposed along one edge of the blank and forming a reinforcement for said edge.

5. In the method of making envelopes or bags, the steps of forming a lengthy strip of sheet material with a plurality of spaced Z-shaped pleats, uniting together the layers of each pleat, cutting out in spaced relation a plurality of envelope or bag blanks from the pleated sheet, the spacing of said blanks being such with relation to the spaced pleats that when each blank is cut from the strip a pleat will be disposed along one of its edges to form a reinforcement for said edge.

6. In the method of making envelopes or bags, the steps of forming a lengthy strip of sheet material with a plurality of spaced pleats extending transversely of the strip, adhesively uniting the layers of each pleat, cutting out in spaced relation a plurality of envelope or bag blanks from the pleated sheet, the spacing of said blanks with relation to the spaced pleats being such that when each blank is out from the strip the edge of said blank employed to subsequently form the mouth of the bag or envelope to be produced from'the blank, will be reinforced by one of the pleats.

' pleats, and folding each blank so cut into bag formation with the mouth of each bag so formed reinforced about its edge by a pleat.

8. The method of making a bag or envelope of sheet material comprising, forming a lengthy strip or sheet material with a plurality of pleats,

, adhesively uniting the layers of said pleats, cutting out bag blanks from the pleated strip so that the bag-mouth-forming edge of each blank so cut is formed by one of the pleats and a closure flap on each blank is formed by a continuation of one of the layers of each pleat, and folding each blank so formed into bag formation with the mouth of each bag so formed reinforced about its edge by a pleat.

9. In the method of making envelopes, bags and similar containers, the steps of forming a section of sheet material with a pleat, uniting the layers of the pleat together, and cutting an envelope or bag blank out of the section with one edge of the blank so out composed of one edge of the pleat, said pleat constituting a reinforcement for the mouth of the bag to be formed from the blank so cut.

10. In the method of making envelopes, bags or similar containers, the steps of forming a lengthy strip of sheet material with a pleat extending longitudinally of the strip, uniting by adhesion the layers of thepleat, cutting out a plurality of envelope or bag blanks from the pleated strip, with the same edge of all of the blanks so but formed by the pleat.

11. In the method of making envelopes, the steps of forming a single continuous pleat in a lengthy strip of sheet material, uniting the overlapping portions of the pleat, and cutting out envelope blanks in side-by-side relationship from the pleated strip in such a manner that the top edge of each blank so cut will be composed of a portion of the pleat cut out of the strip as a part of the blank.

12. In the method of making envelopes, the steps of forming a single continuous pleat in a lengthy strip of sheet material, with said pleat extending longitudinally of the strip and at one side of the? longitudinal center line thereof, unitingthe overlapping parts of the pleat and cutting out envelope blanks in side-by-side relationship from the pleated strip in such a manner that the top edge of each blank so cut will be composed of a portion of the pleat cut out of the strip as a part of the blank.

JULES J. BRELL. HARRY RADZINSKY. 

